It is common practice to form concrete slabs over spaced apart beams or walls. The forms normally used in such construction projects to support the concrete while it hardens include wooden spanner beams supporting plywood panels. The spanner beams are suspended on hangers between the main structural girders or walls and the plywood panels are installed on top of the spanner beams to provide a flat surface for receiving the concrete. After the concrete has hardened sufficiently to become self-supporting, the forms are generally disassembled and removed for further use.
The types of hangers currently used to support the spanner beams suffer from various disadvantages, such as structural weakness, high cost, and assembly and disassembly difficulties. Also, since most existing hangers receive the spanner beam relatively loosely, the assembled forms lack rigidity and are able to shift in position or even collapse when the concrete is poured. Known hangers are further unsatisfactory in that the disassembly and removal of the forms require considerable time and effort and often result in damage to the forms or the hangers. More importantly, the disassembly or "wrecking" of the forms involves danger to the workmen because the spanner beams and plywood panels are released together and the entire bulk of the forms, therefore, must be handled simultaneously.
Another disadvantage of many of the prior art joist hangers is that they are constructed of a number of parts, many of which can be misplaced or lost by workmen prior to or after use. Further, many of the prior art joist hangers are constructed of materials which are subject to being ruined by being bent or fractured while being disassembled or transported between various construction sites.
In view of the foregoing drawbacks associated with existing joist hangers, an object of the present invention is to provide an improved hanger assembly.
More specifically, it is an object of the invention to provide a joist hanger assembly which supports a spanner beam in a rigid position between a pair of spaced girders or concrete block walls.
Another object of the present invention is to provide a joist hanger which is capable of tightly retaining the joist between the spanner beams or walls and yet which can be readily removed when disassembly is desired.
Another object of the invention is to provide a joist hanger which permits the assembly and disassembly of the forms to be carried out quickly, easily, and safely.
Yet another object of the present invention is to provide a joist hanger that is economically manufactured and yet constructed ruggedly for repeated use.
Still another object is to provide a joist hanger which can be a unitary sturdy article eliminating the possibility of lost hanger portions during disassembly and transportation.
Other objects, aspects, and advantages of the present invention will become apparent to those skilled in the art, having had the benefit of this disclosure and its accompanying drawings.